It has been a long, strange journey from Coney Island, where Mr. Epstein grew up in middle-class surroundings. He taught briefly at Dalton, the...

It has been a long, strange journey from Coney Island, where Mr. Epstein grew up in middle-class surroundings. He taught briefly at Dalton, the Manhattan private school, and then joined Bear Stearns, becoming a derivatives specialist. He struck out on his own in the 1980s.

His business is something of a mystery. He says he manages money for billionaires, but the only client he is willing to disclose is Leslie H. Wexner, the founder of Limited Brands.

As Mr. Epstein explains it, he provides a specialized form of superelite financial advice. He counsels people on everything from taxes and trusts to prenuptial agreements and paternity suits, and even provides interior decorating tips for private jets. Industry sources say he charges flat annual fees ranging from $25 million to more than $100 million.